Low-temperature 1-color Pyrometer
This classification includes one color infrared pyrometers measuring range is 250℃-2200℃. The one color pyrometers currently on market are mostly narrow-band pyrometers. Its principle of temperature measurement is to determine the temperature by detecting the radiant energy that occurs in a narrow wavelength range of an object. The temperature a pyrometer measured is the average temperature in an area, and the measuring result is affected by emissivity, lens contamination and background radiation.
To use 1-color pyrometer mode, the measured area of the object should be large (it can fully fill the target field of view) , object surface should be relatively flat (not curved), measurement direction should less than 30 degrees, and the physical and chemical state of the measured object surface should be stable (not in the process of oxidation, gasification or liquefaction) , the optical channel should with less dust and without blocking and attenuation.
1-color pyrometer, monochromatic infrared pyrometer, one color pyrometer, one-color infrared pyrometer Changzhou Sijie Optoelectronics Technology Co.,Ltd. , https://www.sjinfrared.com
Water ring heat pump system variable water volume operation and its related problems
In the real estate industry, water ring heat pump air conditioning systems have gained widespread adoption due to their high efficiency compared to traditional air-cooled systems, ease of independent billing, and cost-effectiveness. However, these systems also face operational challenges, particularly in terms of energy consumption by pumps during transitional seasons or when only a few users are active. The key question is: how can we reduce the power consumption of the pumps under such conditions?
Currently, many real estate projects use sub-district, independently controlled water ring heat pump units. Each district or household manages its own cooling system, opening and closing based on demand. While this allows for individual control and metering, it also leads to inefficiencies in shared components like pumps and cooling towers, which are often billed proportionally. This raises the need for an optimized approach to pump operation, especially during low-load periods.
To address this, several strategies have been proposed. First, each unit should be equipped with a two-way valve that opens and closes in sync with the unit. Second, the pump on the unit side should start and stop based on whether any valve is open. Third, the unit-side pumps can be controlled via variable frequency drives based on supply and return water pressure. Fourth, pump sizing must consider the load characteristics to avoid overdesign. Lastly, the cooling tower (or boiler) side pump should operate based on temperature thresholds—starting when the return temperature exceeds 32°C or drops below 16°C.
One critical issue is the configuration of the unit-side pumps. When using variable speed pumps, two main concerns arise: avoiding resonance between the pump's vibration frequency and the isolator’s natural frequency, and preventing the pump from entering the surge zone due to changes in pipeline characteristics caused by closed valves. These factors must be carefully considered during pump selection.
Let’s take an example: a project with a total cooling water flow of 600t/h, where the minimum load could drop to 5% of design capacity. Three pumps, each with a flow of 200t/h, are typically installed. At 5% load, the pump speed would need to drop significantly, potentially causing resonance with the isolator. To prevent this, a smaller pump (e.g., 75t/h) may be added to handle lower loads efficiently.
The control system for variable volume operation usually relies on DDC (Direct Digital Control), offering advantages such as energy savings, lower costs, and easy scalability. Each floor or area has a local controller that communicates with a central system to manage pump operations based on valve signals. When all units are off, the system shuts down the pumps. As more units activate, the pumps adjust their speed to maintain pressure balance.
For the cooling tower side, the pump operates based on return water temperature, ensuring efficient operation of the cooling system. This setup helps optimize energy use across different load scenarios.
An economic analysis of the system shows significant energy savings. For instance, with variable-speed pumps, the annual power consumption was reduced by nearly 50% compared to fixed-volume systems. This highlights the importance of proper pump configuration and control in achieving energy efficiency in water ring heat pump systems.
In summary, while water ring heat pump systems offer many benefits, optimizing pump operation through variable speed control and smart configuration is essential for reducing energy costs and improving overall system performance. Whether the system runs at low load for extended periods or not, careful planning ensures both efficiency and reliability.